My wife loves the idea of 2 guys being so horny they will get each other off. This has led to bi action with some of her fuck buddies.
One of her well hung friends feeds me his cock so I can swallow him before he gets hard. It just too big once he is fully erect. He fucks her brains out and occasionally she watched while he finishes in my mouth......he cums a lot. Another favorite of hers was a fuck buddy who was more gay than straight but loved having her pussy to use. She'd sit on my back and make out with im while feeding his cock into me. She liked seeing his hands on my hips pulling me on to his cock and telling me I was not getting away as he fucked me.